feeling the heat after a disappointing debate, team obama comes out swinging. meantime, mitt romney gets personal and big bird breaks his silence on snl. >>> danger zone? on this football night in america, a growing fight off the field. kids caught in the middle. >>> and american classics. once the heart of millions of homes, the new efforts to give a lot of old castaways new life. >>> good evening. there may very well be more than just frost on the pumpkin where you are tonight. we start this evening with a cold blast. a dramatic and practically overnight temperature swing has turned what had been an exceptionally mild fall for most of the country into a big chill that tonight is gripping roughly two-thirds of the nation. scores of low temperature records have been broken over the last 24 hours as the mercury went from the 70s and 80s in many places down into the 30s and 40s, even below freezing. we'll get the outlook for the week ahead in a moment, but we start with nbc's michelle fra frandsen here in new york. michelle, good evening. >> good evening, lester.